How to Improve Recovery Rates in Low-Grade Gold Ore?

With the gradual depletion of high-grade gold resources, low-grade gold deposits have become a key focus in current gold mining operations. However, such deposits typically exhibit challenges such as low gold content, fine-grained mineralization, and abundant impurities, leading to difficult processing and low recovery rates. Consequently, optimizing recovery rates through appropriate mineral processing techniques and equipment configuration has become a priority for mining enterprises.

1. Key Characteristics of Low-Grade Gold Deposits

Low-grade gold ores typically exhibit the following characteristics:

First, they possess low gold grades, necessitating the processing of large volumes of ore to achieve viable yields.

Second, gold is predominantly distributed as fine or ultrafine grains within gangue minerals, presenting significant challenges for liberation.

Third, they often contain sulfides, carbonaceous materials, or clay minerals, which adversely impact the beneficiation process.

These characteristics necessitate the adoption of more refined and systematic beneficiation approaches for low-grade gold ores.  

2. Key Beneficiation Processes for Improving Recovery Rates

(1) Rational Crushing and Grinding Processes

Effective recovery from low-grade gold deposits hinges on thorough liberation of useful minerals. Employing multi-stage crushing and closed-circuit grinding processes, while rationally controlling grinding fineness, enhances gold mineral liberation without over-grinding, thereby creating favorable conditions for subsequent separation.

(2) Gravity Preconcentration Process

For low-grade gold ores containing coarse grains or partially free gold, gravity preconcentration stages—such as centrifugal concentrators or jigs—can be incorporated before or during grinding. This recovers a portion of gold early, boosting overall recovery rates while reducing the processing load on subsequent stages.

(3) Enhanced Recovery via Flotation

When gold predominantly exists as fine grains or sulfide inclusions, flotation becomes the primary method for boosting recovery rates. By rationally selecting collectors, frothers, and adjusting flotation circuit structures, the recovery efficiency of gold and associated valuable minerals can be significantly improved.

(4) Application of Combined Processes

In practical production, single processes often fail to meet recovery demands for low-grade gold ores. Employing combined processes like “gravity separation + flotation” or “flotation + leaching” represents an effective contemporary approach to improving recovery rates for low-grade gold ores.

3. Impact of Equipment Selection on Recovery Rates

The performance of mineral processing equipment directly influences the treatment effectiveness of low-grade gold ores. High-efficiency ball mills, energy-saving classification equipment, high-performance flotation machines, and advanced gravity separation devices can enhance mineral processing indicators while reducing energy consumption, all while maintaining processing capacity.

4. Conclusion

The key to improving recovery rates in low-grade gold ore lies in thoroughly analyzing ore properties, rationally matching mineral processing workflows, and selecting stable, adaptable processing equipment. Through systematic design and process optimization, low-grade gold ore can also achieve favorable economic benefits.